An example to show how to build a Plone add-on compliant for both Plone 4 and Plone 5.
It is a very simple add-on generated with mr.bob.
It contains:
- a basic Dexterity type (named Task),
- a CSS and a JS (chart.css and chart.js),
- a view (/@@all-tasks) which draw a ugly chart about the tasks and which involves chart.css and chart.js.
There are 3 Generic Setup installation profiles for installing:
- base, which contains the non version-specific setup (in our case, that's the Task content-type),
- plone4, which contains JS and CSS declaration for Plone 4, and depends on base,
- plone5, which contains JS and CSS declaration for Plone 5, and depends on base.
The plone4 or plone5 profile will automatically imported when we install the add-on depending on the portal's current version.
Similarly, for unistalling, there are 3 Generic Setup installation profiles (uninstall-base, uninstall-plone4 and uninstall-plone5), and it works the same way.
The Plone 5 approach regarding CSS and JS is based on the current front-end development practices. So when we develop the front-end part of our add-on, we might create patterns, have a bunch of LESS files for theming, etc. (see Mockup ), and at the end the all thing is compiled into one single JS and one single CSS, which are declared in a bundle.
In our case, we do not want to use the Plone 5 front-end stack because it would not apply to Plone 4, making the project less maintainable. So the trick is to declare our existing original chart.css and chart.js as a bundle directly (even if they are not the result of any compilation). Here is how we do it (in registry.xml):
<records prefix="plone.bundles/examplep4p5"
interface='Products.CMFPlone.interfaces.IBundleRegistry'>
<value key="enabled">True</value>
<value key="jscompilation">++resource++example.p4p5/chart.js</value>
<value key="csscompilation">++resource++example.p4p5/chart.css</value>
<value key="last_compilation">2016-01-01 00:00:00</value>
<value key="compile">False</value>
<value key="depends">plone</value>
</records>The project is licensed under the GPLv2.